Loss of structural water and carbonate of Nd:YAG laser-irradiated human enamel

Autor(es)

Correa-Afonso, Alessandra Marques ^[1] ; Bachmann, Luciano ^[2] ; de Almeida, Cintia Guimaraes ^[1] ; Palma Dibb, Regina Guenka ^[3] ; Borsatto, Maria Cristina ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Clin Infantil, Fac Odontol Ribeirao Preto Odontol Prevent & Soci, BR-14040904 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Dept Fis, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Fac Odontol Ribeirao Preto, Dept Odontol Restauradora, BR-14040904 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 30, n. 4, p. 1183-1187, MAY 2015.
• Citações Web of Science: 6

Resumo

The objective of this study was to use Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) to assess whether Nd:YAG laser irradiation associated with a dye or not alters the chemical constitution of the enamel. Fourteen enamel sections were randomly divided into two groups: (1) Nd:YAG and (2) dye + Nd:YAG. First, the untreated enamel surfaces were analyzed by FTIR to acquire the control absorption spectrum. Next, Group 2 received a layer of inactivated coal diluted in deionized water before laser treatment. Enamel samples belonging to groups 1 and 2 were then irradiated with a 1,064-nm Nd:YAG laser (80 mJ, 10 Hz) in the contact mode; the carbonate absorption band and the water absorption band were measured in each sample after irradiation. The water band was measured again 24 h, 48 h, and 7 days after irradiation. Group 1 had statistically similar water and carbonate contents before and after irradiation. Group 2 displayed significantly lower (p < 0.05) water content after irradiation, which remained constant along time at 24 and 48 h. After 7 days, the water content increased slightly, being statistically higher than in the other experimental periods, except for the control. The carbonate/phosphate ratio was measured only at the beginning, and after irradiation, it decreased only in Group 2 indicating carbonate loss (p < 0.05). Irradiation with 1,064-nm Nd:YAG laser associated with a dye reduces the carbonate and structural water content in the enamel. (AU)

• Processo FAPESP: 10/06861-0 - Influência da irradiação dos lasers Nd:YAG e CO2 na composição química e ultra-estrutural do esmalte dental
• Beneficiário: Alessandra Marques Corrêa Afonso
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 03/13489-6 - Caracterização de tecidos dentais duros após irradiação laser e tratamento químico: avaliação da composição, estrutura e resistência química
• Beneficiário: Luciano Bachmann
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores